1. Field of the Invention
This invention relates to power distribution units or assemblies of the type used in the wiring systems for buildings and particularly to a distribution unit which can receive a power source and redistribute the source power in three or more distributed circuits.
2. Description of the Prior Art
It is now common practice to provide electrical services to buildings by means of wiring systems of the type described in U.S. Pat. No. 4,740,167, incorporated herein by reference. Wiring systems of the type described in that patent specification comprise electrical cables having connectors on their ends, junction boxes, and duplex receptacles which are plugged into the junction boxes. The junction boxes contain a plurality of bus bars which are connected to the conductors in the cable when the connectors on the cable ends are coupled to the junction boxes. The bus bars in turn have integral receptacles for tab terminals so that when the duplex receptacles are plugged into the junction box, the bus bars are connected to the outlet receptacles in the duplex receptacles. It is common practice to use these receptacles in modular offices, mounting these junction boxes in walls or panels, in particular, in cutout openings within sheet metal walls. The wiring interconnecting these junction boxes is generally electrical power cable, surrounded by a metal conduit, and electrically interconnected to an electrical power connector.
This type of electrical cable, so-called pre-wired cable, is also useful in ceiling electrical systems for powering the lights, for electrical distribution within environmental air areas, or for electrical distribution in raised floor systems. One of the shortcomings of this type of system is the distribution of branch circuits from a single source circuit. Many of these type wiring circuits are hard wired, spliced together by way of plastic "wire nuts" which screw down over three base conductors to common them together. However, U.L. does not recommend more than 3 wires to be so commoned, as the fourth would be trapped only by the round surfaces of the other three, making the electrical connection of the fourth questionable.
It is an object of the invention then to provide an electrical power distribution unit having easy electrical connection and disconnection thereof.
It is a further object of the invention to provide an electrical power distribution unit for use with three or four branch circuits from a common source.
It is a further object of the invention to provide an electrical power distribution unit capable of distributing more than one complete circuit to prevent overloading any one circuit.
Other objects and advantages of the invention will be apparent from the following description, the accompanying drawings and the appended claims.